[TYPO3-commerce] Max 1 Coupon

[Bing van Moorsel | Idar Creative]

Info:
Typo3: 4.2.8
Commerce: 0.10.1 (do not want to update due to some adjustments)
Commerce coupon: Latest forge 0.2.0

Hallo list,

Im making a coupon system for my webshop. i got most things running. I can 
add coupons, they show correctly in my basket and stuff works great.

howerver i cant find any option/way to set a maximum amount of coupons you 
can use at the same time.
I dont want people to be able to use multiple coupons. 1 order = 1 coupon 
max.

what i found out sofar is that the coupon extention uses the 
"syscoupons_special" article from the product COUPONS in SYSTEM categorie. 
Now what i want is that you can only have 1 product from COUPONS in your 
basket.

is there any way i can do this?
either in the coupons or in the artikels/products?

Greetings,

Bing